Akiko Ohku is best known for directing comedies about lonely single women on the lookout for love, including her 2017 breakout hit, “Tremble All You Want.” Mayu Matsuoka starred as a nerdy office worker obsessed with ammonite fossils and a teenage crush she never got over.

But as Ohku’s latest, “She Taught Me Serendipity,” shows, her films are not purely rom-coms. When the stories turn serious, their protagonists’ pain becomes all too real.

“She Taught Me Serendipity” is the director’s first to center on a guy — a quirky, immature college student. But the two women who enter his small world both have strong personalities; he is a weak reed by comparison.